I just bought a 1993 miller maxtron 450 with a s22a feeder and found out they're obselete. It was replaced by the XMT 456. The maxtron series only were produced for 5 years. The power source and feeder look and run like brand spankin new. I'm alittle nervous about it being junk. Any info or oppinions on whether I should keep it or dump it while I can still get my money back. Theirs alot of used ones out there today, but ?